While I knew about the existance of File::Basename, the last time I looked at
it I don't believe it was part of Perl Core. I should have suspected, but
now it is a standard Perl module that makes this trivial:

use File::Basename;

# Retrieve just the filename

my $filename_only = basename($filename);

# Get just the path in this filename

my $path_only = dirname($filename);

You can get even fancier with the fileparse() function provided in
this module.

my ($base, $path, $suffix) = fileparse( $filename );

Would yield the filename only in $base, the path in $path, and
nothing in $suffix. This is because we did not provide a regular
expression to match on.

If we instead used:

my ($base, $path, $suffix) = fileparse( $filename, qr{\.txt} );

And we ran it against $filename = '/home/frank/test.txt' and
$filename2 = '/home/frank/test.doc' it would give us:

Base: test
Path: /home/frank
Type: .txt

and

Base: test.doc
Path: /home/frank
Type:

If the filename give to fileparse() does not match, it is not
stripped from the basename.

It just goes to show that no matter how long you've been using Perl, or how much you think you know, there is always something out there you could be learning.

Comments

I discovered exactly this fact last month and it simplified some work greatly in a setting where I could not add modules from CPAN. Another advantage to this module is that it handles Windows files and even those from some other operating systems with unusual separators.

To the Pythonistas reading this: Python has similar modules in the standard distribution, going way back to early releases, so use it as well.

by Bobbie The Programmer on Aug 6, 2007 at 10:21 AM

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